1. Field of Invention
The present invention relates generally to orthodontic devices and more particularly to the selection of materials used in orthodontic archwires, brackets and other appliances used to apply corrected forces to maloccluded teeth.
2. Description of Prior Art
The practice of orthodonture is the use of various appliances to correct the malocclusion of teeth. During this corrective procedure it is often necessary to impart a variety of forces to the teeth to move the teeth to their final desired positions. Typically this is achieved through a use of variety of different appliances either simultaneous or consecutively. One of the most common appliances used in orthodontics is an orthodontic archwire which is secured to orthodontic brackets, which in turn are attached to the teeth of the patient. Although attempts have been made to make archwires, brackets and other device portions of plastic, resins, ceramic and glass fibers, these attempts have been generally unsuccessful, because plastic, resins, ceramic and glass fibers are unable to carry the high tensile loads over the periods of time required in orthodontic devices. Thus, in general archwires and brackets must be made from high tensile strength metal in order to carry the loads and forces. However, metal braces are regarded by many as cosmetically unattractive and in some cases is the primary reason why patients may be reluctant to subject themselves to orthodonture.
What is needed is a material which may be used for orthodontic appliances such as archwire and brackets which is capable of carrying the tensile loads of metal, is not subject to the material limitations of plastics, resins, ceramic and glass fibers, and yet is transparent or nearly transparent or translucent so as to visually blend with the natural color of the teeth on which the appliances are mounted.